1. Field of the Invention
The present invention relates to a package and a method of packing endless belts, and more particularly to a package and a method of packing belt-shaped photoreceptors, intermediate transfer belts, feeding belts, etc. for use in an electrophotographic apparatus.
2. Discussion of the Background
Electrophotographic technologies are widely used for, e.g., printers connected with facsimiles and personal computers as well as copiers, and particularly their high-resolution and full-color images are eminently progressed in recent times. In addition, on-demand printers using the electrophotographic technologies come into the market.
In electrophotographic apparatuses using the electrophotographic technologies, various belts such as belt-shaped electrophotographic photoreceptors, intermediate transfer belts and feeding belts are used. Recent technology regarding these belts is discussed in, e.g., “Digital Hardcopy Technology” published by Kyoritsu Shuppan Kabushiki Kaisha on Nov. 15, 2000 (Nonpatent Literature 1).
As this literature mentions, the recent full-color, high-resolution, high-speed electrophotographic apparatus or on-demand printing electrophotographic apparatus has a belt-shaped electrophotographic photoreceptor, an intermediate transfer belt or a feeding belt, which have a long peripheral length. In addition, in such an apparatus, the belt-shaped electrophotographic photoreceptor, intermediate transfer belt or feeding belt is required to have extremely high uniformity and smoothness.
For example, when the belt-shaped electrophotographic photoreceptor has a concavity and convexity, an image development irregularity occurs in the image developing process, resulting in a problem of partly faded or diminished images.
In addition, when the intermediate transfer belt has a concavity and convexity, an image development irregularity occurs in an image developing process, resulting in a problem of partly faded or diminished images as well. When the feeding belt has a concavity and convexity, a feeding displacement occurs, resulting in image displacements. As mentioned above, in the recent electrophotographic apparatuses, a belt-shaped electrophotographic photoreceptor, an intermediate transfer belt, a feeding belt or the like is required to have high uniformity and smoothness. Accordingly, these belts are required not to have a concavity and convexity or a damage when stored or transported.
The following conventional methods of packing these belts are suggested and disclosed. For example, Japanese Patent Publication No. 3-44299 discloses a method of covering the entire surface of an endless belt-shaped photoreceptor with a releasable light-shield protection sheet. Japanese Laid-Open Patent Publication No. 8-6436 discloses a method of using a flat plate material having a cut as a buffer material to fix a photoreceptor. Japanese Laid-Open Patent Publication No. 9-269624 discloses a method of perpendicularly containing a photoreceptor belt, in which the belt is held in the air in a container with an elastically deformable core material inserted into an inside portion of the belt, which is longer than a width portion of the belt to prevent its edge from bending, and further a protection sheet is wound around an outside of the belt. Japanese Laid-Open Patent Publication No. 9-319259 discloses a method of winding a nonwoven fabric made of a synthetic fiber around a photoreceptor belt as a protection sheet. However, although these methods are effective for packing a conventional belt having a short peripheral length, e.g. , of not longer than 500 mm, none of them are sufficient for packing a belt having a long peripheral length. Namely, even when a photoreceptor belt, an intermediate transfer belt or a feeding belt having a peripheral length of not longer than 500 mm are packed in a box as they are, although they occupy a large area thereof, they can be stored and transported without having a concavity and convexity or without damage.
However, when the belt has a long peripheral length, e. g., longer than 500 mm, the packing container becomes too large or the belt is shaken and abraded so as to be damaged while being transported. As a method of packing a belt having a long peripheral length without such problems, the following method is conventionally used:
(1) three (paper) tubes which are as long as a width of a belt or longer than the width thereof are prepared;
(2) the belt is expanded to the maximum and a first tube and a second tube are put inside at each end of the belt;
(3) a third tube is put on the belt surface at either end thereof; and
(4) the belt is wound toward the other end thereof until the three tubes become lined up.
This packing method is actually used for Ricoh Imagio MF530, etc.
However, the present inventors found that the following two problems can occur even in this method.
One is that the paper tube typically used in this method and is a so-called spiral paper tube-which is formed by obliquely winding a tape-shaped paper with an adhesive around a mandrel because it has a low production cost, and the spiral paper tube obliquely has a slight concavity and convexity on a surface thereof. Conventionally, the spiral paper tube is used for packing belts such as photoreceptor belts, and even though the belts consequently has a slight concavity and convexity or a damage, the resultant images are not affected. However, in the recent high-quality, high-resolution and full-color image electrophotographic apparatus, even such a concavity and convexity of a photoreceptor is not conventionally a problem which affects the resultant images. Specifically, in a halftone image, the image density fades in the shape of an oblique stripe having a width of a few mm because the photoreceptor belt has a concavity and convexity. Although the concavity and convexity is very slight, it can be found by putting the belt on a flat desk without tension and observing reflected light from a surface thereof using an illumination on a ceiling.
The other problem is that when the above-mentioned packing method using three tubes is used, a portion between the tubes is slightly damaged on occasion. For example, when a belt shaped photoreceptor is packed using three paper tubes A, B and C, the photoreceptor surface between the paper tubes A and B has a linear damage. In addition, the surface between the paper tubes B and C also has a linear damage. This damage is so slight that it is not a problem for the conventional electrophotographic apparatus, but is a serious problem for recent high-quality, high-resolution and full-color image electrophotographic apparatuses. Specifically, in a halftone image, the image density fades in the shape of an oblique stripe having a width of a few mm because the photoreceptor belt has a concavity and convexity or is damaged. Although the concavity and convexity or the damage is very slight, it can be found by putting the belt on a flat desk without tension and observing reflected light from a surface thereof using an illumination on a ceiling.
Because of these reasons, a need exists for a package and a method of packing endless belts such as belt-shaped photoreceptors, intermediate transfer belts and feeding belts used in the recent high-quality, high-resolution and full-color image electrophotographic apparatuses without the occurrence of a concavity and convexity, an undesirable habitual characteristic (i.e., a habit) or being damaged.